Regulation of Genes Involved in Carnitine Homeostasis by PPARαacross Different Species (Rat, Mouse, Pig, Cattle, Chicken, and Human)

Abstract

Recent studies in rodents convincingly demonstrated that PPARαis a key regulator of genes involved in carnitine homeostasis, which serves as a reasonable explanation for the phenomenon that energy deprivation and fibrate treatment, both of which cause activation of hepatic PPARα, causes a strong increase of hepatic carnitine concentration in rats. The present paper aimed to comprehensively analyse available data from genetic and animal studies with mice, rats, pigs, cows, and laying hens and from human studies in order to compare the regulation of genes involved in carnitine homeostasis by PPARαacross different species. Overall, our comparative analysis indicates that the role of PPARαas a regulator of carnitine homeostasis is well conserved across different species. However, despite demonstrating a well-conserved role of PPARαas a key regulator of carnitine homeostasis in general, our comprehensive analysis shows that this assumption particularly applies to the regulation by PPARαof carnitine uptake which is obviously highly conserved across species, whereas regulation by PPARαof carnitine biosynthesis appears less well conserved across species.